There is doubt, and then there is doubt. Cardinal Newman memorably said that ten thousand difficulties do not add up to a doubt. He is speaking of doubt as a decision against, or at least a withholding of consent. The act of faith does not preclude but invites curiosity and interrogation, but that is not doubt. I think I know what people mean when they say that faith includes doubt, but that can also be misleading. It is frequently said that Mother Teresa’s "dark night of the soul” illustrates the power of doubt in creating a sustained crisis of faith. A lovely little book just issued I Loved Jesus in the Night by Paul Murray, offers a different perspective on the nature of her anguish. “In the case of Mother Teresa, it was not simply the darkness weighing on her inner heart which constituted the anguish of the night. What most troubled her spirit was what she called ‘this torturing longing for God.' Thus, on November 6, 1958, she wrote: ‘I did not know that love could make one suffer so much. –That was suffering of loss—this is of longing—of pain human but caused by the divine.' In this state, John of the Cross explains, the soul lives by one thing only: namely, the driving force of a fathomless desire for union with God.' And, as a result, the absences of the Beloved which the soul suffers . . . are very painful; some are of such a kind that there is no suffering comparable to them."' There is suffering in being lost, and there can be greater suffering in being found.
--Richard John Neuhaus, “While We’re At It,” First Things, #188 (Dec. 2008), p. 66.